In this paper we calculate the transport coefficients of
plasmas formed by air and water vapor mixtures. The
calculation, which assume local thermodynamic equilibrium
(LTE) are performed in the temperature range from 500 to
12000 K. We use the Gibbs free energy minimization method to
determine the equilibrium composition of the plasmas, which is
necessary to calculate the transport coefficients. We use the
Chapman-Enskog method to calculate the transport
coefficients. The results are presented and discussed according
to the rate of water vapor. The results of the total thermal
conductivity and electrical conductivity show in particular that
the increasing of the rate of water vapor in air can be
interesting for power cut. This could be improve the
performance of plasma during current breaking in air
contaminate by the water vapor.